Someone else might have something better, but I'd probably just use a portable carpet cleaner with regular solution which goes in it. It should leach most or all of the brake fluid out of the carpet ... I doubt you'll get all of it out, but it shouldn't be too big of a deal. Clean it a couple of times and you should be golden. If you don't have the equipment, take it to a car detail shop, tell them what you want, and have them do it. They'll have techniques and equipment to get it out without an issue.
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*Note:Brake fluid is water soluble so you don't need special cleaners such as a de-greaser. A wet vac with soap and water is suitable to resolve the issue.